Keeping Your Focus

•036-041-ETS_60-Plugged-In-2By John Bigelow.

Moving from a standard video camera, whether it be a handy cam or a semi pro video camera, to a DLSR involves a number of challenges. For people who are used to shooting with a video camera, a DSLR adds a variety of options that they perhaps had not given much thought to on their video camera.

For teachers used to teaching photography who are now looking at moving to teaching video as well, there are a few differences that need to be considered.

The great thing about modern DSLR cameras, such as the Sony A7, many of the new Canon cameras ranging from the 70D to the 5DMkIII, and so on, is that students can now enjoy the benefits of a full frame sensor – or very close to a full frame sensor, which gives their projects a more film-like look. However, better, larger image sensors are only useful if the image is in focus. And while this might sound like an obvious statement, it is amazing how easy it is for students to get this wrong.

Almost every camera on the market today features some type of auto focus, so it would be fair to assume that getting sharp images is easy. However, the challenge with auto focus is to ensure that focuses on the right thing, and that it stays on the right thing throughout the shot. For example, an auto focus function will often tend to focus on the strongest source of light. Therefore, if a student is trying to focus on a person’s face, but the camera wants to focus on the brightly lit sign just behind the person, you might not always pick this up by looking at the image on the small 3.5 inch view finder.

Secondly, it is not uncommon for the auto focus on a camera to jump around during a shot, changing the focal point depending on the activity in the shot. There are a number of ways to work around these issues.

For the sake of expedience, we will confine our discussion to shooting scenes with people in them. When focussing on a person, it is standard practice to focus on the subject’s eyes as this is where people tend to look. Therefore, in order to get the best result, set the camera to manual focus. This might be something you have to do from the camera’s settings and it might also require you to switch the lens to manual – there is often a switch on the side of the camera lens.

With the camera set to manual, use the digital zoom function, not the camera’s actual optical zoom, to zoom in as far as possible on the person in the scene and adjust the focus to get a nice clean and sharp focus. Then zoom back out using the digital zoom.

The reason we use the digital zoom as opposed to the optical zoom is that by zooming in manually with the optical zoom, you run the risk of having to change things like exposure and aperture settings to get the shot looking right. Then, when you physically zoom back out, the setting for the shot might be all wrong. However, by digitally zooming in, your settings should remain stable as you are not actually physically changing anything on the camera. You are simply using a greater percentage of the image sensor to create the digital zoom. This allows you to see in more detail, how sharp the focus is on a small view finder. Remember, the smaller the view finder, the more ‘in focus’ everything will look. Therefore, it is easy to assume that things look great even when you have soft focus or the image is completely out of focus.

In ‘run and gun’ type situations, where students might be shooting in the field or pressed for time, another quick fix you might try is to simply switch the camera into auto photograph mode and shoot a picture. You can then switch back to video mode and the setting in most cameras will remain the same.

For those schools with the budget to spend a little on additional equipment, another possible solution involves the use of external devices such as a screen loupe or a field monitor.

A screen loupe is simple a device that fits over the LCD viewer on most DLSR cameras (you would need to source the one specific to your camera). The screen loupe eliminates external sources of light and shadow from the view finder, allowing you to focus more on the detail being displayed and achieve a sharper, clearer image. Some screen loupe’s, like the Zacuto Z-Finder Pro 3.0x for 3.2″ screens magnifies the image from the LCD viewer by up to three times.

Field monitors also provide a range of additional tools and are for those school AV departments that really want to teach students to use professional grade equipment. A field monitor is simply a larger, high resolution version of the LCD monitor you already use on the back of the camera. However, due to the larger screen size and the increased resolution, a field monitor makes it much easier to achieve sharper focus.

A field monitor connects to the camera via the DLSR’s internal HDMI port, which obviously means you need a camera with HDMI out in order to use a field monitor. In addition to providing the ability to achieve sharper focus, many field monitors include a range of additional tools, such as wave form monitors and histogram functions so that users can check exposure, colour balance and a range of other elements in the shot prior to commencing filming.

A field monitor also allows the student acting as videographer to consult with other students who may be filling the roles of director or producer to ensure that the framing of the shot is exactly what the director or teacher is looking for. It also gives the teacher a tool via which he or she can discuss the composition of the shot with students in real time as part of a lesson, helping the students make changes and improvements on the fly.

Focus is critical. A slightly under or over exposed shot can always be corrected in post-production but focus cannot be changed, and an out of focus shot is the type of thing that is avoidable but will make a video unwatchable.


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Education Technology Solutions has been created to inspire and encourage the use of technology in education. Through its content, Education Technology Solutions seeks to showcase cutting edge products and practices with a view to expanding the boundaries and raising the standards of education curricula. It introduces teachers and IT staff to the latest products, services and developments in education technology with a view to providing practical how-to guidance designed to facilitate the integration of those products and services into the school environment in the most productive and beneficial manner possible.

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